uboot-envtools: update to 2018.03
[openwrt/openwrt.git] / tools / mkimage / patches / 090-reproducible-SOURCE_DATE_EPOCH.patch
1 From f3f431a712729a1af94d01bd1bfde17a252ff02c Mon Sep 17 00:00:00 2001
2 From: Paul Kocialkowski <contact@paulk.fr>
3 Date: Sun, 26 Jul 2015 18:48:15 +0200
4 Subject: [PATCH] Reproducible U-Boot build support, using SOURCE_DATE_EPOCH
5
6 In order to achieve reproducible builds in U-Boot, timestamps that are defined
7 at build-time have to be somewhat eliminated. The SOURCE_DATE_EPOCH environment
8 variable allows setting a fixed value for those timestamps.
9
10 Simply by setting SOURCE_DATE_EPOCH to a fixed value, a number of targets can be
11 built reproducibly. This is the case for e.g. sunxi devices.
12
13 However, some other devices might need some more tweaks, especially regarding
14 the image generation tools.
15
16 Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
17 ---
18 Makefile | 7 ++++---
19 README | 12 ++++++++++++
20 tools/default_image.c | 21 ++++++++++++++++++++-
21 3 files changed, 36 insertions(+), 4 deletions(-)
22
23 --- a/README
24 +++ b/README
25 @@ -4928,6 +4928,18 @@ within that device.
26 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
27 virtual address in NOR flash.
28
29 +Reproducible builds
30 +-------------------
31 +
32 +In order to achieve reproducible builds, timestamps used in the U-Boot build
33 +process have to be set to a fixed value.
34 +
35 +This is done using the SOURCE_DATE_EPOCH environment variable.
36 +SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
37 +option for U-Boot or an environment variable in U-Boot.
38 +
39 +SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
40 +
41 Building the Software:
42 ======================
43
44 --- a/tools/default_image.c
45 +++ b/tools/default_image.c
46 @@ -89,6 +89,9 @@ static void image_set_header(void *ptr,
47 struct image_tool_params *params)
48 {
49 uint32_t checksum;
50 + char *source_date_epoch;
51 + struct tm *time_universal;
52 + time_t time;
53
54 image_header_t * hdr = (image_header_t *)ptr;
55
56 @@ -97,9 +100,25 @@ static void image_set_header(void *ptr,
57 sizeof(image_header_t)),
58 sbuf->st_size - sizeof(image_header_t));
59
60 + source_date_epoch = getenv("SOURCE_DATE_EPOCH");
61 + if (source_date_epoch != NULL) {
62 + time = (time_t) strtol(source_date_epoch, NULL, 10);
63 +
64 + time_universal = gmtime(&time);
65 + if (time_universal == NULL) {
66 + fprintf(stderr, "%s: SOURCE_DATE_EPOCH is not valid\n",
67 + __func__);
68 + time = 0;
69 + } else {
70 + time = mktime(time_universal);
71 + }
72 + } else {
73 + time = sbuf->st_mtime;
74 + }
75 +
76 /* Build new header */
77 image_set_magic(hdr, params->magic);
78 - image_set_time(hdr, sbuf->st_mtime);
79 + image_set_time(hdr, time);
80 image_set_size(hdr, sbuf->st_size - sizeof(image_header_t));
81 image_set_load(hdr, params->addr);
82 image_set_ep(hdr, params->ep);